US9093740B2 - Antenna-in-package structure - Google Patents

Antenna-in-package structure Download PDF

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Publication number
US9093740B2
US9093740B2 US13/574,062 US201113574062A US9093740B2 US 9093740 B2 US9093740 B2 US 9093740B2 US 201113574062 A US201113574062 A US 201113574062A US 9093740 B2 US9093740 B2 US 9093740B2
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Prior art keywords
radiating element
antenna
layer
electronic device
ground plane
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US20120293392A1 (en
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Christopher Barratt
Chakib El Hassani
Pascal Ciais
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INSIGHT SIP Sas
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INSIGHT SIP Sas
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04—Resonant antennas
    • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
    • H01Q9/0421—Substantially flat resonant element parallel to ground plane, e.g. patch antenna with a shorting wall or a shorting pin at one end of the element
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/242—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
    • H01Q1/243—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use with built-in antennas
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
    • H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04—Resonant antennas
    • H01Q9/30—Resonant antennas with feed to end of elongated active element, e.g. unipole
    • H01Q9/42—Resonant antennas with feed to end of elongated active element, e.g. unipole with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Definitions

  • the present invention relates generally to the field of antennas and more specifically to miniature antennas of the kind used in electronic portable and handheld devices to receive and transmit signals in a multi gigahertz range.
  • the invention is more particularly related to electronic devices such as miniaturized communication modules or antenna in package.
  • a cellular phone e.g.: a GSM mobile phone (Global System for Mobile communications) also embeds a BluetoothTM short range wireless link to connect the phone to another device; typically, to connect to a personal computer or to a mobile headset.
  • GSM Global System for Mobile communications
  • BluetoothTM short range wireless link to connect the phone to another device; typically, to connect to a personal computer or to a mobile headset.
  • GPS Global Positioning System
  • PDAs Personal Digital Assistants
  • a wireless LAN Local Area Network
  • IFA inverted F antenna
  • PCB printed circuit board
  • the invention intends to miniaturize systems of the antenna in package type which is a recent technology separate from conventional antenna-on-PCB solutions.
  • the invention relates an electronic device comprising:
  • the invention also describes an antenna of the antenna-in-package type (AIP). which comprises an upper surface on which a radiating element is provided.
  • the radiating element has an open end and a feeding end.
  • the antenna also comprises an adaptation element.
  • the antenna is characterized in that the adaptation element is provided at an area that is different from the upper surface of the antenna holding the radiating element.
  • the adaptation element is connected, at one end, to an intermediate point of the radiating element and grounded at another end.
  • the invention also includes following optional features:
  • the antenna according to one embodiment is of the type antenna-in-package and is selected from a list comprising: IFA, PIFA, monopole and dipole antennas.
  • An antenna according to one embodiment is such that said adaptation element is integrated into an electronic circuit and is electrically connected to said AIP antenna.
  • FIG. 1 depicts an example of a standard folded inverted F antenna (IFA) implemented on a printed circuit board along with the respective quality and efficiency curve.
  • IFA folded inverted F antenna
  • FIG. 2 illustrates the way invention manages to further reduce the size of the exemplary IFA antenna, along with the respective quality and efficiency curve.
  • FIG. 3 illustrates how a good impedance adaptation can be retrieved with the modified antenna structure of the invention along with the respective quality and efficiency curve.
  • FIG. 4 illustrates an alternate way of using the available area to obtain better results in term of transmission efficiency, showed along with the respective quality and efficiency curve.
  • FIG. 5 illustrates yet another usage of the available area to implement an antenna according to the invention, showed along with the respective quality and efficiency curve.
  • FIG. 6 depicts another embodiment with respect to the adaptation element.
  • FIG. 7 shows an embodiment of integration of the antenna in an electronic device.
  • FIG. 1 describes a standard folded inverted F antenna implemented on a PCB, an antenna structure which is largely used in all sorts of handheld and portable communicating devices.
  • the main parameters of the antenna geometry that allows its best adaptation to the signal wavelength to transmit and receive are shown.
  • this type of antenna devised to operate at a quarter of the transmitted wavelength signals, i.e.: about 12 cm in this example of a 2.45 GHz antenna
  • the length of the folded leg 120 is thus close to 3 cm.
  • the other parameters that participate to the adaptation of the electrical characteristics are: the width of the traces 122 ; the repetition step of the folded motifs 124 ; the height of the folded motifs 126 ; their distance to the PCB ground plane 128 .
  • the whole antenna structure 130 is situated off the ground plane 140 of the PCB 150 .
  • the grounded end of the antenna is connected, directly or through vias, to the PCB ground plane 145 while the antenna is directly fed, typically from a radio transceiver housed on the PCB, through its intermediate leg 155 .
  • This type of structure is often referred to as “antenna in package” (AIP) since it is printed on the same PCB or substrate that holds all the components of the communicating device. Thus, does not require any tuning and skilled personnel when assembled in the communicating box.
  • S 11 is one parameter of the so-called scattering parameters (S-parameters) that are commonly used to measure and qualify the behaving of linear passive or active circuits operating at radio frequencies. S-parameters are used to evaluate electrical properties of these circuits such as their gain, return loss, voltage standing wave ratio (VSWR). In a 2-port circuit, S 11 , one of four possible S-parameters in a 2 ⁇ 2 matrix, measures the input port voltage reflection coefficient.
  • S-parameters scattering parameters
  • Radiation efficiency is the ratio between the power actually radiated by the antenna versus the one injected by the transceiver through the feeding leg 155 . The difference contributes to produce heat that must be dissipated by the antenna resistance. Obviously, the closer to 100% this value the better it is.
  • This parameter is plotted in diagram 170 as a function of the radiation angle in the vertical (Z) plane, referred to as ⁇ 172 , measured in degree from the vertical axis.
  • the efficiency 174 is constant in the Z plane and is here of 55.3%.
  • FIG. 2 illustrates the way that the invention manages to further reduce the size of the exemplary standard antenna as shown in FIG. 1 .
  • FIG. 3 illustrates how a good impedance adaptation can be retrieved with a modified radiating antenna structure, printed on a single plane or layer of the laminate substrate (PCB), which takes advantage of the above observation.
  • PCB laminate substrate
  • the antenna of the invention is comprised, on a same plane of the PCB, of a radiating trace having a feeding end 355 , an open end 334 and an intermediate connection point 332 that is grounded through a non radiating 20 trace or element 345 situated on another plane of the PCB.
  • the non-radiating element or matching element 345 acts as an adaptation element for matching the impedance of the antenna to input impedance of the rest of the device.—i.e.—the electronic circuit embedded in the device.
  • the electronic circuit typically includes components such as a radio transceiver and printed wired traces serving as electrical links.
  • the device comprises a first layer 330 where the radiating element is located and at least one layer 320 (consisting in or incorporating the ground plane). At least one of the first layer 310 and the ground plane layer 320 may be an outer layer of the multilayered wiring structure.
  • FIG. 4 illustrates an alternate way of using the invention in which the available area 431 (6 ⁇ 8 mm) is used to obtain a better result in term of transmission efficiency 470 .
  • the same folded antenna structure 430 is enlarged to occupy the whole available area.
  • the efficiency obtained here is of 60.5% to be compared with the efficiency of 55.3% of the device shown in FIG. 1 .
  • the feeding leg 455 is grounded in a similar way as illustrated in previous FIG. 3 .
  • Parameter S 11 and the bandwidth of this antenna are shown in diagram 460 .
  • Bandwidth 464 is compared to the bandwidth 462 of the reference antenna of FIG. 1 and found to be slightly wider.
  • the adaptation is also slightly better, as in reference number 466 , and found to be of ⁇ 13.8 dB at 2.47 GHz.
  • the slight shift observed of the central frequency, from 2.45 GHz for the reference antenna, can easily be corrected by further adjusting the geometry of the antenna.
  • FIG. 5 illustrates with reference number 530 , yet another usage of the available area to implement an antenna according to the invention.
  • the transmission efficiency 570 is further increased to reach 65.0% so well above the efficiency of a conventional device as shown in FIG. 1 with an efficiency of about 55.3%.
  • the behavior of parameter S 11 is, as shown at 560 , similar to what was observed in FIG. 4 , i.e., an increase of the bandwidth and a better adaptation with a low value of ⁇ 16.8 dB and a slight shift of the central frequency to 2.47 GHz.
  • the radiating element which is still a printed wired element—has a folded structure extending from the feeding end 355 located above the ground plane 340 towards the open end 334 which is located at an area of the layer opposite the area facing the ground plane.
  • the folded structure comprises a plurality of parallel sections oriented transversally compared to the situation of previous figures.
  • the adaptation element has a longitudinal main direction that is parallel to the sections of the folded radiating elements.
  • adaptation element and the radiating element face each other since it optimizes the reduction of space needed for the whole antenna structure.
  • FIG. 6 shows a further embodiment with a refined shape for the adaptation element 345 .
  • the element is here formed with printed wired sections folded at right angle with a longitudinal direction bordering the ground plane 340 .
  • FIG. 6 also shows that the adaptation element 345 may be included in a layer 320 situated under the first layer 310 .
  • the layer 320 of the substrate incorporates the ground plane 340 but the ground does not cover the whole surface area of the layer 320 . Indeed, a portion of the layer 320 is not covered by the conducting ground surface and is simply an insulated portion.
  • the adaptation element 345 is located at the border between the ground surface referenced 340 and the free surface of the layer 320 , thus facing a preferably small area of the radiating element of the antenna.
  • the ground plane 340 and the adaptation element 345 are directly connected at 342 .
  • the radiating element comprises a folded wired section made of several parallels portions and the width of the portions is increasing from the feeding end 355 to the open end 334 .
  • the width increase may be continuous along the radiating element.
  • the width of the terminal portion of the antenna may be between 1.5 and 3 times wider than the width of the first portion (the one of the feeding leg 455 ).
  • FIG. 7 shows an embodiment of the device according to the invention wherein the radiating element of the antenna is located on a first layer of a laminate substrate 702 .
  • This layer also receives a transceiver 701 , an oscillator 704 such as crystal and possibly electronic components of the surface mount technology.
  • Underlayers comprise a layer 320 incorporating the ground plane 340 and connection pads 703 for external connections.
  • An overmold 705 is used to encapsulate the entire circuit of the board thus forming an overmolded packaging.
  • the structure of the invention allows a reduction of the area occupied by an antenna or, within the same available area, an improvement of the bandwidth and efficiency of the antenna, all other things being equal.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Details Of Aerials (AREA)
  • Support Of Aerials (AREA)
  • Waveguide Aerials (AREA)
US13/574,062 2010-01-20 2011-01-19 Antenna-in-package structure Active 2031-06-27 US9093740B2 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP10305066.2 2010-01-20
EP10305066A EP2348578A1 (en) 2010-01-20 2010-01-20 Improved antenna-in-package structure
EP10305066 2010-01-20
PCT/EP2011/050653 WO2011089141A2 (en) 2010-01-20 2011-01-19 Improved antenna-in-package structure

Publications (2)

Publication Number Publication Date
US20120293392A1 US20120293392A1 (en) 2012-11-22
US9093740B2 true US9093740B2 (en) 2015-07-28

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US (1) US9093740B2 (enExample)
EP (2) EP2348578A1 (enExample)
JP (1) JP5690845B2 (enExample)
CA (1) CA2786507C (enExample)
WO (1) WO2011089141A2 (enExample)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170201006A1 (en) * 2016-01-12 2017-07-13 Asustek Computer Inc. Wireless communication circuit and electronic device
US9881882B2 (en) 2016-01-06 2018-01-30 Mediatek Inc. Semiconductor package with three-dimensional antenna

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6163381B2 (ja) * 2013-08-08 2017-07-12 株式会社メガチップス パターンアンテナ
JP6621418B2 (ja) 2014-03-26 2019-12-18 トムソン ライセンシングＴｈｏｍｓｏｎ Ｌｉｃｅｎｓｉｎｇ 誘電体装荷を伴うアンテナ構造
US10164338B2 (en) * 2015-08-25 2018-12-25 Qualcomm Incorporated Multiple antennas configured with respect to an aperture
TWI620278B (zh) * 2016-07-13 2018-04-01 矽品精密工業股份有限公司 電子封裝件及其製法
US11201119B2 (en) 2018-06-06 2021-12-14 At&S Austria Technologie & Systemtechnik Aktiengesellschaft RF functionality and electromagnetic radiation shielding in a component carrier
CN110167261B (zh) * 2019-06-26 2024-11-05 京信网络系统股份有限公司 毫米波有源天线单元及pcb板间互连结构

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US7936318B2 (en) * 2005-02-01 2011-05-03 Cypress Semiconductor Corporation Antenna with multiple folds
JP2007124328A (ja) * 2005-10-28 2007-05-17 Shinko Electric Ind Co Ltd アンテナおよび配線基板
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US6452548B2 (en) * 2000-02-04 2002-09-17 Murata Manufacturing Co., Ltd. Surface mount antenna and communication device including the same
US20020024466A1 (en) 2000-08-31 2002-02-28 Yoshiyuki Masuda Pattern antenna and wireless communication device equipped therewith
US6512493B2 (en) * 2001-07-02 2003-01-28 Samsung Electro-Mechanics Co., Ltd. Chip antenna
US6917346B2 (en) * 2001-09-07 2005-07-12 Andrew Corporation Wide bandwidth base station antenna and antenna array
US7362271B2 (en) * 2002-01-18 2008-04-22 Matsushita Electric Industrial Co., Ltd. Antenna apparatus, communication apparatus, and antenna apparatus designing method
US20030184482A1 (en) * 2002-03-04 2003-10-02 Ulrich Bettin Multi-band PIF antenna with meander structure
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9881882B2 (en) 2016-01-06 2018-01-30 Mediatek Inc. Semiconductor package with three-dimensional antenna
US10340235B2 (en) 2016-01-06 2019-07-02 Mediatek Inc. Semiconductor package with three-dimensional antenna
US20170201006A1 (en) * 2016-01-12 2017-07-13 Asustek Computer Inc. Wireless communication circuit and electronic device
US10170820B2 (en) * 2016-01-12 2019-01-01 Asustek Computer Inc. Wireless communication circuit and electronic device

Also Published As

Publication number Publication date
CA2786507A1 (en) 2011-07-28
JP2013517727A (ja) 2013-05-16
JP5690845B2 (ja) 2015-03-25
EP2545611B1 (en) 2017-08-23
WO2011089141A2 (en) 2011-07-28
WO2011089141A3 (en) 2011-09-29
US20120293392A1 (en) 2012-11-22
CA2786507C (en) 2017-08-01
EP2348578A1 (en) 2011-07-27
EP2545611A2 (en) 2013-01-16

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